STL Map of list<string>

[Maikeru]

I am trying to create a map that contains a string as the key and a list of strings as the value. Essentially it will be a dictionary where the key is an English word and the list will contain all Latin equivalents. My program reads from a file containing Latin words and their English equivalents. I am using the operator[] from map so that I can add to the list<string> should the Key already exist in my map. I am not sure of the syntax that I need to be using for this. The operator[] returns a reference to the element, should I be storing this reference in a map iterator? I get an error when I attempt this

mit = unit[key];

mit is my map iterator, unit is my map, and key is the string I am attempting to store in the map.

[Ganon11]

You could also do something like this:

1) Use the map's find() operation to get the pair<string, list<string> > containing your key and its value (the list).
2) Manually add your new value to the list.

I'm not sure how you could correctly overload the operator[], but my guess is you'd have to return a reference to the value type - in this case, returning a list, not a map iterator.

[Maikeru]

You could also do something like this:

1) Use the map's find() operation to get the pair<string, list<string> > containing your key and its value (the list).
2) Manually add your new value to the list.

I'm not sure how you could correctly overload the operator[], but my guess is you'd have to return a reference to the value type - in this case, returning a list, not a map iterator.

I was actually misunderstanding the problem that I am having. Basically the compiler doesn't like that I am trying to insert just the key into the map so it is expecting a pair. In order to properly insert a pair, (i am using insert() now) how would I go about this considering my value is a list? Should I be passing the key and a list that I create prior to calling insert or should I be passing the key and the string value that I want in the list?

[Laharl]

You have a map<string, list<string> >. To insert to a preexisting value list, use map[key].*appropriate list insert method*. If the list does not exist beforehand, create it before insertion.

For example:

map<string, list<string> > etol;
string e = "speak", l1="loquor", l2="voco";
list<string> k;
k.push_back(l1);
etol.insert(pair<string, list<string> >(e, k);
etol[e].push_front(l2);
//"speak" now maps to a list of "voco", "loquor"
 

[Maikeru]

Thanks for all of your help! I have got it working now for the most part. Just a few formatting tweaks to be made. Thanks again.